如何使用Gradle构建源jar

task sourcesJar(type: Jar, dependsOn: classes) {    classifier = 'sources'    from sourceSets.main.allSource}task javadocJar(type: Jar, dependsOn: javadoc) {    classifier = 'javadoc'    from javadoc.destinationDir}artifacts {    archives sourcesJar    archives javadocJar}